Method and apparatus for working on submerged conduit means

ABSTRACT

A method and apparatus for working on submerged conduits entailing the use of a conduit manipulating and aligning frame and a working chamber. The aligning frame straddles independently movable conduit portions. A plurality of clamps engages each conduit portion and the clamps are manipulated to bring the conduit portions into an appropriate alignment. The working chamber straddles the aligned conduit portions and provides a controlled, relatively dry atmosphere within which conduit repairing, connecting or other operations may be performed.

United States Patent 1151 3,641,777

Banjavich et al. Feb. 15, 1972 [54] METHOD AND APPARATUS FOR 3,353,364 11/1967 131111111111 m1. ..61/69 WORKING ON SUBM R ED CONDUIT 3,477,236 11/1969 Burrus... ..61/72.3 x

MEANS 3,500,648 3/1970 Daniell ..6l/69 3,508,410 4/l970 Lynch ..6l/69 [72] Inventors: Mark P. Baniavich; George R. Morrissey,

both of New Orleans; Anthony V. Gaudi- Primary Examiner-J. Karl Bell 8110, rie, all of La. AttarneyBums, Doane, Benedict & Mathis [73] Assignee: Taylor Diving 8: Salvage Co., Inc., New

Orleans, Jefferson Parish, La. [57] ABSTRACT I A method and apparatus for working on submerged conduits [22] July 1969 entailing the use of a conduit manipulating and aligning frame [21] App]. No.: 841,777 and a working chamber.

The aligning frame straddles independently movable conduit [52] U.S. Cl ..61/69, 61/723 portions. A plurality of clamps engages each conduit portion [51] and the clamps are manipulated to bring the conduit portions [58] Field of Search ..6l/69, 72.3, 81, 82 into an appropriate alignment.

The working chamber straddles the aligned conduit portions [56] Rem-em cued and provides a controlled, relatively dry atmosphere within UNITED STATES PATENTS which conduit repairing, connecting or other operations may be performed. 3,204,417 9/1965 Robley ..61/72.3 3,267,682 8/1966 Robley ..6 1 /72.3 1 20 Claims, 28 Drawing Figures 7l6 3l 6 3 315 1 256 L 17 7l4 n5 r-7l8 7Ol f I 7 2 /7 -7o2 a. i 1. 7'2 I06 103 104 105 I g 1 l I: T 1' :l :I 1

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INVENTOBS MARK P. BANJAVICH GEORGE A. MORRISSEY ANTHONY V. GAUDIANO PATENTEBFEB 15 I972 SHEET 15 0F 15 Jr TORNEYS BY ar/w, bow, 20.201105, Mac/cu. $11

METHOD AND APPARATUS FOR WORKING ON SUBMERGED CONDUIT MEANS GENERAL BACKGROUND, OBJECTS AND SUMMARY OF INVENTION For some time, it has been recognized that underwater working chambers may be advantageously employed to provide a relatively dry atmosphere surrounding a submerged conduit, where conduit work operations are to be performed.

For example, when it is desired to interconnect two adjacent ends of submerged conduit portions, a working chamber may be located over the adjacent portions so as to provide a relatively dry and isolated work zone. This zone permits operations such as the welding of the conduit ends to be performed.

However, as offshore operations are projected into progressively more difficult operating environments, it becomes clear that more is necessary than merely an underwater working chamber.

From the standpoint of the safety of divers and the efficiency and feasibility of operations, it would be desirable to effectively stabilize the conduit upon which operations are to be performed and provide reliable means for insuring the appropriate alignment of conduit portions.

It would also be highly desirable to provide a conduit stabilizing arrangement which would insure that the conduit means upon which operations are to be performed are effectively secured in position.

Since, in many instances, operations may be performed where strong currents are present and where such currents may contain substantial amounts of suspended silt or sand, it would be desirable to provide an underwater work chamber, the operability of which would not be destroyed in the event that solid materials were deposited in substantial quantities adjacent the exterior of the working chamber.

It is particularly necessary of course to insure that any working chamber affords optimum diver safety conditions and permits divers to leave the working chamber, regardless of adverse conditions in the vicinity of the exterior of the working chamber.

From the standpoint of insuring an effective working environment, it is desirable that the working chamber should provide for both humidity and temperature control.

Since the working chamber may be conditioned by a particular gaseous environment, it is desirable that simple but effective means be provided for preventing the escape of such a special gaseous environment from the working chamber interior.

Where a conduit stabilizing and aligning frame is utilized in conjunction with a working chamber, the efficiency of the conduit end alignment operation could be facilitated by the provision of alignment control means operable either from the exterior or interior of the working chamber.

These and other objects of the invention are accomplished, at least in part, by an apparatus including frame means operable to be lowered from floating vessel and be positioned over submerged conduit means. This frame means includes a first plurality of clamp means spaced longitudinally of a first portion of the conduit means and clampingly engageable therewith. A second plurality of clamp means, carried by the frame means, spaced longitudinally of a second portion of the conduit means, is clampingly engageable with this second portion. Clamp-actuated means enable the clamp means of the first and second plurality to be independently manipulated to selectively exert independent conduit portion manipulating force on the conduit means.

The apparatus may also include a working chamber means, or habitat," including a closed diver passage providing communication between the exterior of the working chamber means and an upper exterior portion of its body means.

In a preferred arrangement, the working chamber means is provided with dehumidifying means operable to control both humidity and temperature within the working temperature means. This dehumidifying means preferably includes heat exchanger means disposed in heat exchanging relation with water surrounding the working chamber means.

The apparatus may also include sequentially operable guide means operable to guide the frame means and working chamber means between a floating vessel and the conduit means site. The guide means may also enable a diver transfer chamber to be guided from the floating vessel to the diver passage of the working chamber means.

It is also contemplated that both the frame means and the working chamber means may be provided with a plurality of independently controllable jack means. Such jack means will exert selective lifting force on a submerged surface adjacent the work site.

The installation of the frame means and working chamber means may be facilitated by the use of a bar means which is operable to stabilize and transmit lifting and lowering force between a floating vessel and the frame means or working chamber means, depending upon which of these means the bar means is connected with.

The control means included in the apparatus preferably includes alternately operable control stations, some mounted on the frame means exterior of the working chamber and some mounted on the interior of the working chamber means. Such control means enable the clamp means to be actuated and controlled by divers from the exterior of the working chamber means prior to the installation of the working chamber means and from the interior of the installed working chamber means.

The invention also contemplates a method of working on conduits wherein a plurality of forces are independently exerted at longitudinally spaced locations on each of two independent conduit portions. These forces are exerted so as to insure the appropriate alignment of the conduit portions. A working chamber is positioned over the conduit portions and its interior atmosphere is selectively dehumidified and temperature adjusted.

DRAWINGS In describing the invention, reference will be made to preferred embodiments shown in the appended drawings.

In the drawings:

FIG. 1 schematically illustrates the guiding of an alignment frame downwardly from a floating vessel toward two independently movable conduit portions;

FIG. 2 illustrates the positioning of the alignment frame so as to straddle the two conduit portions, and further illustrates the guiding of a working chamber into position over the conduit portions;

FIG. 3 illustrates the guiding of a diver transfer chamber toward a diver passage of the working chamber, which chamber is disposed so as to straddle the two conduit portions;

FIG. 4 illustrates the arrival of the diver transfer chamber at the diver passage of the working chamber;

FIG. 5 provides an enlarged, transverse, cross-sectional view of the FIG. 4 disposition of the system, illustrating the completed alignment of the diver transfer chamber and the diver passage of the work chamber, and further illustrating the manner in which divers may safely move from the diver transfer chamber through the diver passage to the interior of the working chamber;

FIG. 6 schematically illustrates a power arrangement which may be used to facilitate the guided movement of the diver transfer chamber toward the working chamber;

FIG. 7 provides a fragmentary, perspective view of the alignment frame illustrated in FIG. 1;

FIG. 8 provides a representative, end elevational view of one of four clamping assemblies included in the FIG. 7 alignment frame, with this clamping assembly being viewed along the view direction 8-8 of FIG. 7;

FIG. 9 provides an enlarged view of an articulated, conduit clamp incorporated in the representative FIG. 8 assembly;

FIG. 10 provides a transverse sectional view of the FIG. 9 assembly as viewed along the section line l0 l0;

FIG. 1 1 provides an enlarged transverse sectional view of a clamp hinge as viewed along the section 1 111 of FIG. 9;

FIG. 12 provides an enlarged, side elevational view of the lifting bar shown in FIG. 1 in supporting engagement with the FIG. 7 alignment frame;

FIG. 13 provides a top, plan view of the FIG. 12 lifting bar;

FIG. 14 provides a bottom, plan view of the FIG. 12 lifting bar;

FIG. 15 provides an end elevational view of one embodiment of the working chamber as shown in FIG. 2, illustrating a door associated with a working chamber end wall in a closed door position; FIG. 16 illustrates the FIG. 15 chamber, with the door in an open position so as to define a recess of the reception of a conduit during the working chamber lowering operation shown in FIG. 2;

FIG. 17 illustrates a modified form of the working chamber shown in FIGS. 15 and 16, wherein the working chamber is provided at each of its four corners with a selectively operable jack;

FIG. 18 provides a top plan view of the FIG. 17 embodiment of the working chamber;

FIG. 19 provides an end elevational view of a modified form of the FIG. 15 working chamber wherein the end wall door is provided with a modified actuating arrangement;

FIG. 20 illustrates the FIG. 19 embodiment, with the end wall door in an open position for the reception of a conduit during the working chamber lowering operation;

FIG. 21 provides a vertically sectioned elevational view of a representative jack which may be associated with either the working chamber, as shown in FIG. 17, or the alignment frame, shown in FIG. 7;

FIG. 22 provides a fully sectioned and enlarged view of the upper portion of the FIG. 21 jack, illustrating in vertical section, the arrangement of the jack piston and its seal components;

FIGS. 23a and 23b, when joined along the dividing line a a, illustrate hydraulic circuitry employed to selectively control the actuation of the alignment frame clamps from either the frame or the interior of the working chamber;

FIG. 24 provides a perspective view of the interior of the working chamber, in any of its embodiments, illustrating a diaphragm seal disposed between a conduit portion and the end wall of the working chamber in the vicinity of an end wall door;

FIG. 25, in a perspective, exploded format, illustrates components of the FIG. 24 diaphragm seal;

FIG. 26 provides a transverse sectional view of the FIG. 24 diaphragm seal, as viewed along the section line 26-26 of FIG. 24; and

FIG. 27 provides a schematic illustration of a dehumidifying and temperature controlling system for regulating the humidity and temperature of the working environment within any of the various embodiments of the working chamber.

MAJOR COMPONENTS Major components of the apparatus of this invention are schematically illustrated in FIGS. 1 through 4.

As shown in these figures, the apparatus includes an aligning frame 1, a working chamber or habitat 2, and a lifting and lowering bar 3.

The function of the aligning frame 1 is to provide a stable base, weighing possibly over a hundred tons, on a submerged surface S adjacent a work site. This work site, as shown in FIG. 1, may involve a submerged location beneath a floating vessel V. At this work site, by way of example, two conduits C1 and C2 may be located in generally adjacent positions and be supported by the submerged surface S. The mutually facing ends of the first and second conduit portions C1 and C2 are intended to be connected together as, for example, by a weldedin-place, connecting conduit portion or pup.

Preliminary to the conduit connecting operation, divers may jet or dig away the submerged surface S beneath adjacent end portions of the conduits C1 and C2 to facilitate the conduit joining operation.

The aligning frame 1 is positioned so as to straddle the conduit portions CI and C2. In a manner to be subsequently described, clamps carried by the aligning frame 1 are employed to exert aligning and manipulative forces on each of the conduit portions C1 and C2.

The function of the working chamber or habitat 2 is to provide a relatively dry gaseous atmosphere adjacent the mutually facing ends of the conduit portions C1 and C2. This atmosphere enables conduit connecting or working operations such as welding to be performed with relative facility, ease and efficiency.

The function of the lifting and lowering bar 3 is to facilitate the sequential positioning of the aligning frame 1 and working chamber 2.

Structural details of the frame 1, chamber 2, and bar means 3, and the mode of operation will be subsequently set forth in detail.

In describing the overall invention, principal components will be designated by reference numerals in a hundreds" format, with the initial number corresponding to the principal component involved, i.e., details of the frame 1 will be designated by reference numerals in the series, etc.

ALIGNING FRAME DETAILS Structural details of the massive aligning frame 1 are shown in FIGS. 7 through 11.

As shown in FIGS. 7 and 8, the frame is defined, in part, by two box girders or base stringers 101 and 102. Box griders 101 and 102 are mutually parallel and are operable to engage the submerged surface S on opposite sides of the conduit means C1-C2.

Box girders or base stringers 101 and 102 are transversely interconnected by archlike trusses 103, 104, and 106. The trusses are interconnected by tubular framing, as shown generally in FIG. 7.

Base member connecting, trusses 103 through 106 are substantially identical in structure. Trusses 103 and 106, as shown in FIG. I, are disposed at the end extremities of the base stringers 101 and 102. Intermittent trusses 104 and 105 are positioned so as to provide generally equal spacing between adjacent ones of the trusses 103 through 106.

Each of the trusses 103 through 106 is provided with conduit-engaging clamp means 107.

Representative details of a clamp means 107 associated with the truss 105 are shown in FIGS. 8 through 11.

Thus, clamp 107 includes a first, semicylindrical clamp component 108 and a second, semicylindrical clamp component 109. Components 108 and 109 are pivotally interconnected by an articulation or pivot joint 110 having a pivot axis extending longitudinally of, and parallel to, the base stringers 101 and 102.

Clamp segments 108 and 109 are provided with generally cylindrical conduit engaging faces 110 and 111 respectively. The generally cylindrical conduit engaging faces 1 10 and 111 are intended, in a closed position, to define a generally cylindrical clamp having an axis of curvature extending longitudinally of and parallel to base stringers 101 and 102 and parallel to the pivot axis at articulation joint 110.

As is further shown in FIGS. 9 through 11, clamp engaging face 110 is reinforced by longitudinally spaced and radially extending, arcuate webs 112 and 113. Similarly, in segment 109, conduit engaging face 111 is reinforced by longitudinally spaced and radially extending, arcuate webs 114 and 1 15.

As is shown in FIG. 11, articulation joint 110 is defined by a pivot pin 116. Pivot pin 1 16 is journaled in apertured portions 117 and 118 of plates 114 and respectively. A pair of spaced, platelike webs 119 and 120 welded on the upper extremity of reinforcing web 112 defining a socket 121 within which the upper end of web 114 is received. Pin 116 is journaled in apertured portions of webs 119 and 120, as shown in FIG. 11.

Similarly, spaced platelike webs 124 and 125 are welded to web 113 defining a socket 126. receiving web 115. Pin 116 is journaled in apertured portions 127 and 128 of webs 124 and 125, respectively.

Longitudinally extending lugs 129 and 130 carried by segments 108 and 109 respectively, provide clamp segment securing means. A threaded bolt 131 is operable to pass through apertured portions of lug means 130 and 129 and engage a threaded nut 132. The nut and bolt 131 and 132 manipulated by a diver at the work site, thus engage the lugs 130 and 129 to hold the clamp segments 108 and 109 in a closed position.

In the closed clamp position, it is contemplated that the conduit engaging faces 110 and 111 would be somewhat larger than the outer periphery of the engaged conduit so as to permit relative rotation between the conduit and the closed clamp. Even though such relative rotation would be permitted, in the preferred embodiment, there still would be substantially contiguous and conforming engagement between the faces 110 and 111 and the conduit means preferably.

Each clamp 107 is also provided with clamp actuating means. As shown in FIG. 8, this clamp-actuating means comprises a first piston and cylinder assembly 133, a second piston and cylinder assembly 134, and a third piston and cylinder assembly 135.

First piston and cylinder assembly includes a cylinder 136 pivotably connected to base stringer 101 by a longitudinally extending pivot pin mounting 137. Piston rod 138 projecting from the cylinder 136 is pivotably connected with segment 109 by a longitudinally extending pivot pin connection 139.

Similarly, cylinder component 140 of the second piston and cylinder assembly 134 is connected with base stringer 102 by a longitudinally extending pivot pin connection 141. A piston rod 142 of assembly 134 is pivotably connected to clamp segment 108 by a longitudinally extending pin connection 143.

Third piston and cylinder assembly 135 is mounted within an upwardly converging recess 144 in the apex of the truss or arch 105. Cylinder component 145 of the assembly 135 is pivotably mounted to an upper plate portion 146 of recess 144 by a longitudinally extending pivot pin connection 147. A piston pin component 148 of assembly 135 is pivotably connected to the pivot pin 116 as generally shown in FIG. 11.

As will be apparent by reference to FIG. 8, coordinated operation of the assemblies 133 and 134 is effective to exert laterally directed force on the conduit engaged by the clamp 107. Extension of the piston rod 138 of assembly 133 will exert a force on the clamp 107, directed to the right as shown in FIG. 8, while extension of the piston rod 142 will exert force on the clamp 107 directed to the left as shown in FIG. 8.

Similarly, upward movement of the piston rod 148 will exert a lifting force on the clamp 107 while downward movement of the piston rod 148 will tend to depress the clamp 107.

It is contemplated that each of the assemblies 133, 134, 135 is double acting in nature so that changes in force may be selectively exerted in either axial direction of each assembly.

The manner in which the various assemblies 133-135 may be independently manipulated in a diver-coordinated fashion to effect the desired application of force to a conduit portion engaged by the clamp 107 will be subsequently described.

As will also be apparent by reference to FIG. 2, the clamp segments 107 associated with the trusses 103 and 104 provide first and second, longitudinally spaced clamps clampingly engageable with the conduit portion C1. Either one of the clamps of the trusses 103 and 104 may function as a fulcrum, while the other clamp functions to apply a conduit flexing or moving force to the conduit portion C1. These clamps may also function to apply force in the same general direction to conduit C1.

Similarly, the clamps 107 associated with the trusses 105 and 106 define a second plurality of clamp means spaced longitudinally of the conduit portion C2 and clampingly engageable with this conduit portion.

In this second plurality of clamp means, either clamp 107 may serve as a fulcrum while the other clamp applies a flexing or conduit moving force to the conduit means C2. Here again, these clamps may function in unison to apply force in the same general direction to conduit C2.

The weight or mass of the frame 1 provides a stable base from which clamp forces may be exerted on the conduit means Cl and C2 so as to induce movement of the conduit means C1 and C2 relative to the relatively immovable base 1. Such conduit means movement will serve to adjust the position and/or orientation of conduit portions Cl and C2 so as to bring them into an appropriate degree of alignment for a conduit connecting or other conduit working operation.

In view of the foregoing discussion, it will be clear that the piston and cylinder assemblies associated with the clamp means of the trusses 103 and 104 may be viewed as first clamp-actuating means operable to selectively exert independent force on the conduit means C 1, selectively directed generally transversely of the longitudinal axis of the conduit portion C1. Since the resultant thrust or force vector may be varied by selective operation of the various piston or cylinder assemblies, the applied force is selectively orientable about the cylinders of the conduit portion C1.

In other words, the force applied by any clamp assembly may be adjusted so as to be horizontal, vertical, or inclined, with respect to horizontal and vertical directions. In short, the resultant force applied to the conduit portion C l by either of the clamp assemblies associated with the trusses 103 and 104, although generally radial in nature, may be oriented to conform to virtually any circumferential alignment.

The piston and cylinder assemblies associated with the clamp of the trusses and 106 provide second clamp actuating means including all of the characteristics of the first clamp actuating means, but operable in connection with the second conduit portion C2.

WORKING CHAMBER DETAILS Structural details of the working chamber or habitat 2 are set forth in FIGS. 15 through 26.

FIGS. 15 and 16 illustrate one embodiment of the working chamber 2.

In this embodiment, the chamber 2 is defined by sidewall means 201 and 202 which are interconnected by a generally semicylindrical stop wall 203.

The ends of the working chamber 2 are closed by end walls 204 and 205. Each of the end walls is provided with a downwardly opening recess. The end wall recesses are substantially identical. Thus, representative recess 206 of end wall 204 extends upwardly from the base 207 of the working chamber and terminates in a downwardly facing, arcuate upper end or conduit-engaging terminus 208. Upper end 208 is preferably fabricated from a series of independently removable cylindrical segments. The cylindrical segments of the upper end portion 208 may be sequentially removed to provide an exposed segment 209 having a cylindrical curvature conforming to the conduit periphery to be engaged, in this case the periphery of conduit means C2 shown in FIG. 1.

The various segments of the recess top defining wall means 208 may be interconnected by removable screws. The screw arrangement may be such so as to permit the sequential removal of segments, moving progressively upwardly from small diameter segments to large diameter segments.

Each end wall is also provided with a door which is mounted for pivotal movement about a generally vertical axis and which is also operable to move toward and away from the recess terminus 208. Thus, the wall 204 is provided with a door 210, while the wall 205 is provided with an equivalent door 21 1.

Representative door 210, as shown in FIG. 15, is defined in part by wall means 212. At the upper end of the wall means 212 a conduit-engaging terminus 213 is provided. Terminus 213 is structurally and functionally the same as recess end defining means 208. However, terminus 213 is mounted in a mirror-image relation with respect to means 208 when the door 210 is disposed in a closed position as shown in FIG. 15.

Door 210 supports a cylindrical sleevelike member 214 on one edge, i.e., the right edge as viewed in FIG. 15. Sleeve 214 is fixedly connected to the door 212 by vertically spaced bracket means 215 and 216. Sleeve 214 is slidably journaled in vertically apertured brackets 217 and 218 carried by the end wall 204.

As is shown in FIG. 16, brackets 216 and 215 are disposed on opposite sides of the mounting bracket 217 so as to limit movement of the sleeve 214 relative to the end wall 204. However, the mounting brackets 217 and 218 journal the sleeve 214 for rotational movement about its longitudinal axis so as to define a door hinge having a generally vertical hinge axis.

A pair of piston and cylinder door jack assemblies 219 and 220 serve to induce vertical movement of the door 210 relative to the end wall 204.

The cylinder portion 221 of assembly 219 is connected to end wall 204 by a mounting bracket 222. The piston 223 of assembly 219 is connected to an anchor point 224 fixedly positioned within the interior ofsleeve 214.

As is shown in FIG. 15, when the piston rod 223 is retracted so as to position the door 210 in an upper or closed position, the piston rod 223 as well as the cylinder 221 are telescopically received within the interior of sleeve 214.

Cylinder 25 of assembly 220 is pivotably connected to end wall 204 by mounting bracket 226. Mounting bracket 226 provides a pivot pin connection 227 having a pivot axis extending longitudinally of chamber 2, i.e., parallel to the axis of curvature 228 of the converged terminus means 208 and 213.

Piston rod 229 of assembly 220 is provided at its lower extremity with a hook 230. Hook 230 is detachably engageable with a pin 23] connected by bracket means 232 to door 210.

During the lowering of working chamber 2 the doors 210 and 211 are each disposed in a lowermost and open position corresponding to the position of door 210 shown in FIG. 16. These doors are each moved, in an identical fashion, from the arrangement shown in FIG. 16 to the FIG. 16 position. This door lowering and opening is accomplished, with reference to door 210, by extending piston rod 229 while assembly 219 remains in its contracted position. Thus, assembly 219 holds the door in the upper position shown in FIG. while the extension of rod 229 frees the hook 230 from the latch pin 231. The assembly 220 may then be pivoted clockwise, from the FIG. 15 position, about the pivot pin 227 to free the assembly 220 from the door 210. The door 210 may then be pivoted about the pivoted joint defined by sleeve 214 and mounting brackets 217 and 218 to an open position. The door may then be lowered by extending piston rod 223 so that the door assumes the lower and open position shown in FIG. 16.

With the working chamber doors both disposed as generally shown in FIG. 16, they are operable to be pivoted to a closed position beneath submerged conduit means C1 and C2, engaging the upper portions 208 of the wall recesses in the FIG. 3 arrangement. The thus pivoted doors may then be rehooked with the extended piston rods 229. Both piston rods 223 and 229 of each door may then be raised to cause the doors 210 and 211 to move upwardly and clampingly engage the underside of the conduit means C1 and C2. In the FIG. 3 arrangement, door means 210 would clampingly engage conduit means C2, while door means 211 would clampingly engage conduit means C 1. This clamping engagement, of course, involves the clamping action of the terminus means 203 and 213 on the top and underside of the conduit means. As will be apparent, the closing of doors 210 and 211 at the submerged work site is facilitated by the previously jetted away, or otherwise removed, portions of surface S beneath the site of chamber 2.

Working chamber 2 is provided with a diver passage means 233 as shown generally in FIGS. 15, 16 and 5.

Diver passage 233 is defined by a generally vertical, closed conduitlike, wall means 234 extending generally vertically along the sidewall 202 of the working chamber 2. Diver passage means 233 is thus located externally of the working chamber 2. Wall 234 may be provided with a door 234a to enable diver movement into and out of passage 233 from the side ofchamber 2.

The upper end 235 of diver passage means 233 is open so as to provide an entry and exit point for divers.

The lower end of passage means 233 is provided with an enlarged portion, extending in a generally U-shaped fashion about a lower edge 236 of wall means 202 and upwardly into the interior 237 of the working chamber 2. This enlarged portion 238 provides a U-shaped, diver transfer passage portion 239 permitting divers to move from the vertical passage portion 240 into the interior 237 of the working chamber 2. The movement of divers through passage portions 240 and 239 may be facilitated by ladder-defining, rungs 241 as shown in FIG. 5.

The upper end 235 of diver passage means 233 may be provided with a landing base 244 which in turn supports an upwardly diverging, guide cone assembly 245.

Guide cone assembly 245 is designed to guidingly receive a downwardly moving diver transfer chamber 246. Transfer chamber 246 may correspond, for example, to a diver transfer chamber or vehicle as described in U.S. Banjavich Pat. No. 3,323,312.

With diver transfer chamber 246 guided onto platform 244 by guide cone 245, divers may move through the passage means 240 and 239 while utilizing a life support system (air supply, etc.) 247 operated from the transfer vehicle 246. System 247 is supplied by an umbilical system 248 extending upwardly to the support vehicle or floating vessel V.

Once a diver has entered the interior 237 of working chamber 2, he may utilize a life support system, possibly including masks, operated from the working chamber 2. The life support system or working chamber 2 would be substantially independent of that associated with the transfer vehicle 246. However, the life support system of working chamber 2 would most probably be supported by an umbilical arrangement extending again from the service vessel V.

It is contemplated that the atmosphere within the interior space 237 would be regulated and adjusted from the standpoint of humidity, temperature, and gaseous content.

The temperature and humidity control arrangements will be subsequently described. The gas atmosphere supplied to the interior of space 237 from the vessel V is preferably abnormally high in nitrogen so as to reduce the relative percentage of oxygen present. It is desirable that the oxygen content should be reduced to a minimum level necessary to sustain life. In so reducing the oxygen content, the likelihood of fire or combustion in the working space 237 is appreciably reduced.

As will be appreciated, the relative ratios of nitrogen and oxygen will vary substantially with the depth of the working chamber 2, i.e., with the pressure within the space 237.

Working chamber 2 may be provided with means to facilitate working operations such as the hoist unit 249 illustrated in FIG. 5. The hoist unit 249 could be used to support a conduit portion being cut away or support a conduit portion being welded in place between the space conduit ends Cl and C2.

The moving of articles such as replacement conduit portions, etc., between the exterior and interior of the working chamber is facilitated by pivotably mounted, perforate or gridlike decks 250 and 251. Deck 250, and for that matter, deck 251, may each comprise a perforate or gridlike floor plate pivotably mounted on which hinge means 252 and 253 extend longitudinally of the working chamber. Such hinge means will enable the floor plates 250 and 251 to be pivoted upwardly and ieave a relatively unobstructed opening 254 in the base of the working chamber 2. When the floor plates 250 and 251 are pivoted downwardly to the position shown in FIG. 5, they are secured in this position by abutment means 255 and 2550 carried by the floor plates 250 and 251, respectively, and engageable with upright frame or wall portion of the working chamber interior.

Of course, opening 254 provides direct fluid communication between space 237 and the water surrounding chamber 2.

Working chamber 2 is provided with lifting eyes 256 and 257 spaced longitudinally of and connected with upper wall means 203 as shown in FIGS. 17 and 18. These lifting eyes 

1. An apparatus to facilitate working on submerged conduit means, said apparatus comprising: frame means operable to be lowered from floating vessel means and be positioned over submerged conduit means, said frame means including a first plurality of independently operable clamp means carried by said frame means, spaced longitudinally of a first portion of said conduit means, and clampingly engageable therewith, a second plurality of independently operable clamp means carried by said frame means, spaced longitudinally of a second portion of said conduit means, and clampingly engageable therewith, first clamp-actuating means connected with said first plurality of clamp means and operable to cause each clamp of said first plurality of clamp means to independently and selectively exert independent force on said first portion of said conduit means selectively directed generally transversely of the longitudinal axis of said first portion and second clamp actuating means connected with said second plurality of clamp means and operable to cause each clamp of said second plurality of clamp means to independently and selectively exert independent force on said second portion of said conduit means independently and selectively directed generally transversely of the longitudinal axis of said second portion.
 2. An apparatus as described in claim 1 including, in at least one of said plurality of clamp means: first clamp means defining selectively positionable fulcrum means; and second clamp means operable to flex a portion of said conduit means about said fulcrum means.
 3. An apparatus as described in claim 1 wherein each of said clamp means includes articulated conduit-engaging means; and wherein each of said clamp actuating means includes first piston and cylinder means pivotally mounted on said frame means and operable to exert force on a clamp means in one, generally horizontal, direction; second piston and cylinder means pivotally mounted on said frame means and operable to exert force on said clamp means in a second, generally horizontal, direction generally opposite to said one direction; and third piston and cylinder means pivotally mounted on said frame means and operable to exert force on said clamp means in a generally vertical direction.
 4. An apparatus as described in claim 3 wherein each of said plurality of clamp means includes: first clamp means defining selectively positionable fulcrum means; and second clamp means operable to flex a portion of said conduit means about said fulcrum means.
 5. An apparatus to facilitate working on submerged conduit means, said apparatus comprising: frame means operable to be lowered from floating vessel means and be positioned over submerged conduit means; said frame means including a first plurality of independently oPerable clamp means carried by said frame means, spaced longitudinally of a first portion of said conduit means, and clampingly engageable therewith, a second plurality of independently operable clamp means carried by said frame means, spaced longitudinally of a second portion of said conduit means, and clampingly engageable therewith, first clamp-actuating means connected with said first plurality of clamp means and operable to cause each clamp of said first plurality of clamp means to independently and selectively exert independent force on said first portion of said conduit means selectively directed generally transversely of the longitudinal axis of said first portion and second clamp-actuating means connected with said second plurality of clamp means and operable to cause each clamp of said second plurality of clamp means to independently and selectively exert independent force on said second portion of said conduit means selectively directed generally transversely of the longitudinal axis of said second portion and working chamber means including, body means having a downwardly facing open portion, recessed first and second end walls operable to receive said first and second portions of said conduit means, first and second door means pivotally mounted on said first and second end walls, respectively, and operable to engage said first and second portions of said conduit means, respectively, to at least partially close the recess portions of said first and second end walls, respectively, diver passage means having an open end at an upper exterior portion of said body means, and wall means extending from said open end downwardly along the exterior of said body means and terminating in an opening disposed within the interior of said body means, and means operable to support said working chamber means from lifting means.
 6. An apparatus as described in claim 5 further comprising: first and second diaphragm means carried by said working chamber means and providing flexible diaphragm seals engageable with said first and second portions of said conduit means, respectively.
 7. An apparatus as described in claim 5 further comprising: dehumidifying means mounted on said working chamber means and operable to remove moisture from the interior thereof and selectively vary the temperature of said interior.
 8. An apparatus to facilitate working on submerged conduit means, said apparatus comprising: frame means operable to be lowered from floating vessel means and be positioned over submerged conduit means; said frame means including a first plurality of independently operable clamp means carried by said frame means, spaced longitudinally of a first portion of said conduit means, and clampingly engageable therewith, a second plurality of independently operable clamp means carried by said frame means, spaced longitudinally of a second portion of said conduit means, and clampingly engageable therewith, first clamp-actuating means connected with said first plurality of clamp means and operable to cause each clamp of said first plurality of clamp means to independently and selectively exert independent force on said first portion of said conduit means selectively directed generally transversely of the longitudinal axis of said first portion and second clamp-actuating means connected with said second plurality of clamp means and operable to cause each clamp of said second plurality of clamp means to independently and selectively exert independent force on said second portion of said conduit means selectively directed generally transversely of the longitudinal axis of said second portion, and a plurality of jack means carried by said frame means, each jack means of said plurality being engageable with a submerged surface adjacent said frame means to exert a lifting force on said frame means.
 9. An apparatus to facilitate working on submerged conduit means having first and secOnd positions, said apparatus comprising: working chamber means including, lifting bar means; body means having a downwardly facing open portion, recessed first and second end walls operable to receive said first and second portions of said conduit means, first and second door means pivotally mounted on said first and second end walls, respectively, and operable to engage said first and second portions of said conduit means, respectively, to at least partially close the recess portions of said first and second end walls, respectively, diver passage means having an open end at an upper exterior portion of said body means, and wall means extending from said open end downwardly along the exterior of said body means and terminating in an opening disposed within the interior of said body means, and means operable to support said working chamber means from said lifting bar means; and a plurality of jack means carried by said working chamber means, each jack means of said plurality being independently operable and engageable with a submerged surface adjacent said working chamber means to exert a lifting force on said working chamber means and adjust the elevation of said chamber door means.
 10. An apparatus to facilitate working on submerged conduit means, said apparatus comprising: frame means operable to be lowered from floating vessel means and be positioned over submerged conduit means; said frame means including a first plurality of clamp means carried by said frame means, spaced longitudinally of a first portion of said conduit means, and clampingly engageable therewith, a second plurality of clamp means carried by said frame means, spaced longitudinally of a second portion of said conduit means, and clampingly engageable therewith, first clamp-actuating means connected with said first plurality of clamp means and operable to cause each clamp of said first plurality of clamp means to selectively exert independent force on said first portion of said conduit means selectively directed generally transversely of the longitudinal axis of said first portion, and second clamp-actuating means connected with said second plurality of clamp means and operable to cause each clamp of said second plurality of clamp means to selectively exert independent force on said second portion of said conduit means selectively directed generally transversely of the longitudinal axis of said second portion a first plurality of jack means carried by said frame means, each jack means of said first plurality being independently operably and engageable with a submerged surface adjacent said frame means to exert a lifting force on said frame means; and a second plurality of jack means carried by said working chamber means, each jack means of said second plurality being independently operable and engageable with a submerged surface adjacent said working chamber means to exert a lifting force on said working chamber means.
 11. An apparatus to facilitate working on submerged conduit means, said apparatus comprising: frame means operable to be lowered from floating vessel means and be positioned over submerged conduit means; said frame means including a first plurality of independently operable clamp means carried by said frame means, spaced longitudinally of a first portion of said conduit means, and clampingly engageable therewith, a second plurality of independently operable clamp means carried by said frame means, spaced longitudinally of a second portion of said conduit means, and clampingly engageable therewith, first clamp-actuating means connected with said first plurality of clamp means and operable to cause each clamp of said first plurality of clamp means to independently and selectively exert independent force on said first portion of said conduit means selectively directed generally transversely of the longitudinal axis of said first portion, and second clamp-actuating means connected with said secoNd plurality of clamp means and operable to cause each clamp of said second plurality of clamp means to independently and selectively exert independent force on said second portion of said conduit means selectively directed generally transversely of the longitudinal axis of said second portion, and diver-operable control means for controlling said first and second clamp-actuating means, said control means including, control means mounted on said frame means and operable by divers to cause said first and second plurality of clamp means to clampingly engage said conduit means and exert force thereon.
 12. An apparatus as described in claim 11 further comprising: working chamber means including, body means having a downwardly facing open portion, recessed first and second end walls operable to receive said first and second portions of said conduit means, first and second door means pivotally mounted on said first and second end walls, respectively, and operable to engage said first and second portions of said conduit means, respectively, to at least partially close the recess portions of said first and second end walls, respectively, diver passage means having an open end at an upper exterior portion of said body means, and wall means extending from said open end downwardly along the exterior of said body means and terminating in an opening disposed within the interior of said body means; and auxiliary control means mounted in the interior of said body means of said working chamber means and operable by divers to cause said first and second clamp means to selectively vary force applied to said first and second portions of said conduit means to adjust the axial alignment thereof.
 13. An apparatus to facilitate working on submerged conduit means, said apparatus comprising: frame means operable to be lowered from floating vessel means and be positioned over submerged conduit means; said frame means including a first plurality of independently operable clamp means carried by said frame means, spaced longitudinally of a first portion of said conduit means, and clampingly engageable therewith, a second plurality of independently operable clamp means carried by said frame means, spaced longitudinally of a second portion of said conduit means, and clampingly engageable therewith, first clamp-actuating means connected with said first plurality of clamp means and operable to cause each clamp of said first plurality of clamp means to independently and selectively exert independent force on said first portion of said conduit means selectively directed generally transversely of the longitudinal axis of said first portion and second clamp-actuating means connected with said second plurality of clamp means and operable to cause each clamp of said second plurality of clamp means to independently and selectively exert independent force on said second portion of said conduit means selectively directed generally transversely of the longitudinal axis of said second portion, and guide means extending between said floating vessel means and said conduit means and operable to guide said frame means into longitudinal alignment with said first and second portions of said conduit means.
 14. An apparatus to facilitate working on submerged conduit means, said apparatus comprising: frame means operable to be lowered from floating vessel means and be positioned over submerged conduit means; said frame means including: a first plurality of clamp means carried by said frame means, spaced longitudinally of a first portion of said conduit means, and clampingly engageable therewith, a second plurality of clamp means carried by said frame means, spaced longitudinally of a second portion of said conduit means, and clampingly engageable therewith, first clamp-actuating means connected with said first plurality of clamp means and operable to cause each clamp of said first plurality of clamp means to selectiVely exert independent force on said first portion of said conduit means selectively directed generally transversely of the longitudinal axis of said first portion, and second clamp-actuating means connected with said second plurality of clamp means and operable to cause each clamp of said second plurality of clamp means to selectively exert independent force on said second portion of said conduit means selectively directed generally transversely of the longitudinal axis of said second portion; bar means operable to be engaged with said frame means and engage longitudinally thereof; said bar means being operable to be connected with raising and lowering means on said floating vessel means; working chamber means including, body means having a downwardly facing open portion, recessed first and second end walls operable to receive said first and second portions of said conduit means, first and second door means pivotally mounted on said first and second end walls, respectively, and operable to engage said first and second portions of said conduit means, respectively, to at least partially close the recess portions of said first and second end walls, respectively, diver passage means having an open end at an upper exterior portion of said body means, and wall means extending from said open end downwardly along the exterior of said body means and terminating in an opening disposed within the interior of said body means, and means operable to support said working chamber means from said lifting bars means; diver-operable control means for controlling said first and second clamp actuating means, said control means including, first control means mounted on said frame means and operable by divers to cause said first and second plurality of clamp means of clampingly engage said conduit means and exert force thereon, and second control means mounted in the interior of said body means of said working chamber means and operable by divers to cause said first and second clamp means to selectively vary force applied to said first and second portions of said conduit means to adjust the axial alignment thereof; and first and second diaphragm means carried by said working chamber means and providing flexible diaphragm seals engageable with said first and second portions of said conduit means, respectively.
 15. An apparatus to facilitate working on submerged conduit means, said apparatus comprising: frame means operable to be lowered from said vessel means and be positioned over submerged conduit means; said frame means including a first plurality of clamp means carried by said frame means, spaced longitudinally of a first portion of said conduit means, and clampingly engageable therewith, a second plurality of clamp means carried by said frame means, spaced longitudinally of a second portion of said conduit means, and clampingly engageable therewith, first clamp-actuating means connected with said first plurality of clamp means and operable to cause each clamp of said first plurality of clamp means to selectively exert independent force on said first portion of said conduit means selectively directed generally transversely of the longitudinal axis of said first portion, and second clamp-actuating means connected with said second plurality of clamp means and operable to cause each clamp of said second plurality of clamp means to selectively exert independent force on said second portion of said conduit means selectively directed generally transversely of the longitudinal axis of said second portion; bar means operable to be engaged with said frame means and engage longitudinally thereof; said bar means being operable to be connected with raising and lowering means on said floating vessel means; working chamber means including, body means having a downwardly facing open portion, recessed first and second end walls operable to receive said first and second portions of said Conduit means, first and second door means pivotally mounted on said first and second end walls, respectively, and operable to engage said first and second portions of said conduit means, respectively, to at least partially close the recess portions of said first and second end walls, respectively, diver passage means having an open end at an upper exterior portion of said body means, and wall means extending from said open end downwardly along the exterior of said body means and terminating in an opening disposed within the interior of said body means, and means operable to support said working chamber means from said lifting bar means; a first plurality of jack means carried by said frame means, each jack means of said first plurality being independently operable and engageable with a submerged surface adjacent said frame means to exert a lifting force on said frame means; a second plurality of jack means carried by said working chamber means, each jack means of said second plurality being independently operable and engageable with a submerged surface adjacent said working chamber means to exert a lifting force on said working chamber means; diver-operable control means for controlling said first and second clamp actuating means, said control means including, first control means mounted on said frame means and operable by divers to cause said first and second plurality of clamp means to clampingly engage said conduit means and exert force thereon, and second control means mounted in the interior of said body means of said working chamber means and operable by divers to cause said first and second clamp means to selectively vary force applied to said first and second portions of said conduit means to adjust the axial alignment thereof; and first and second diaphragm means carried by said working chamber means and providing flexible diaphragm seals engageable with said first and second portions of said conduit means, respectively.
 16. An apparatus to facilitate working on submerged conduit means, said apparatus comprising: floating vessel means; frame means operable to be lowered from said floating vessel means and be positioned over submerged conduit means; said frame means including a first plurality of clamp means carried by said frame means, spaced longitudinally of a first portion of said conduit means, and clampingly engageable therewith, a second plurality of clamp means carried by said frame means, spaced longitudinally of a second portion of said conduit means, and clampingly engageable therewith, first clamp-actuating means connected with said first plurality of clamp means and operable to cause each clamp of said first plurality of clamp means to selectively exert independent force on said first portion of said conduit means selectively directed generally transversely of the longitudinal axis of said first portion, and second clamp-actuating means connected with said second plurality of clamp means and operable to cause each clamp of said second plurality of clamp means to selectively exert independent force on said second portion of said conduit means selectively directed generally transversely of the longitudinal axis of said second portion, said first and second clamp means being operable to engage said first and second portions of said conduit means, respectively, while permitting relative rotation between said first and second clamp means and said first and second portions; bar means operable to be engaged with said frame means and engage longitudinally thereof; said bar means being operable to be connected with raising and lowering means on said floating vessel means; working chamber means including, body means having a downwardly facing open portion, recessed first and second end walls operable to receive said first and second portions of said conduit means, first and second door means pivotally mounted on said first and second end walls, respectIvely, and operable to engage said first and second portions of said conduit means, respectively, to at least partially close the recess portions of said first and second end walls, respectively, diver passage means having an open end at an upper exterior portion of said body means, and wall means extending from said open end downwardly along the exterior of said body means and terminating in an opening disposed within the interior of said body means, and means operable to support said working chamber means from said lifting bar means; a first plurality of jack means carried by said frame means, each jack means of said first plurality being independently operable and engageable with a submerged surface adjacent said frame means to exert a lifting force on said frame means; a second plurality of jack means carried by said working chamber means, each jack means of said second plurality being independently operable and engageable with a submerged surface adjacent said working chamber means to exert a lifting force on said working chamber means; diver-operable control means for controlling said first and second clamp actuating means, said control means including, first control means mounted on said frame means and operable by divers to cause said first and second plurality of clamp means to clampingly engage said conduit means and exert force thereon, and second control means mounted in the interior of said body means of said working chamber means and operable by divers to cause said first and second clamp means to selectively vary force applied to said first and second portions of said conduit means to adjust the axial alignment thereof. door jack means operable to cause the first and second door means of said working chamber means to clampingly engage said first and second portions of said conduit means respectively; first and second diaphragm means carried by said working chamber means and providing flexible diaphragm seals engageable with said first and second portions of said conduit means, respectively, dehumidifying means mounted on said working chamber means and operable to remove moisture from the interior thereof and selectively vary the temperature of said interior, said dehumidifying means including, heat exchanger means disposed in heat exchanging relation with water surrounding said working chamber means; and sequentially operable guide means including, first guide means extending between said floating vessel means and said conduit means and operable to guide said frame means into longitudinal alignment with said first and second portions of said conduit means, second guide means extending between said floating vessel means and said first and second portions of said conduit means, extending through said bar means and operable to guide said working chamber means supported by said bar means to cause said recessed wall portions thereof to receive said first and second portions of said conduit means; and third guide means operable to guide a diver transfer chamber between said floating vessel means and said open end of said diver passage means.
 17. A method of working on conduits in a submerged location, said method comprising: independently exerting a series of longitudinally spaced, independent, and transversely direction forces on each of two spaced conduit means to adjust the alignment thereof; on at least one of said conduit means, exerting one force on one portion of said one of said conduit means to provide fulcrum means reacting transversely on said one portion of said one conduit means, and exerting another force on another portion of said one of said conduit means, said other force being exerted on said other portion of said one of said conduit means to tend to move said other portion of said one of said conduit means generally transversely of the one portion of said one of said conduit means against which said fulcrum means is reacting; isolating said alignEd conduit means in a gaseous environment; and selectively adjusting the humidity and temperature of the working environment.
 18. A method of working on conduits in a submerged location, said method comprising: independently exerting a series of longitudinally spaced, independent, and transversely directed forces on each of two spaced conduit means to adjust the alignment thereof; on at least one of said conduit means, exerting one force on one portion of said one of said conduit means to provide fulcrum means reacting transversely on said one portion of said one conduit means, and exerting another force on another portion of said one of said conduit means, said other force being exerted on said other portion of said one of said conduit means to tend to move said other portion of said one of said conduit means generally transversely of the one portion fulcrum means is reacting; isolating said aligned conduit means in a gaseous environment; selectively adjusting the humidity and temperature of the working environment; and during said working, exerting jacking force from a submerged surface on said conduit means to adjust and maintain the alignment.
 19. A method of working on conduits in a submerged location, said method comprising: independently exerting a series of longitudinally spaced independent and transversely directed forces on each of two spaced conduit means to adjust the alignment thereof; isolating said aligned conduit means in a gaseous environment; selectively adjusting the humidity and temperature of the working environment; and during said working, sequentially exerting said forces on said conduit means under the control of divers located externally and the internally of said working environment.
 20. A method of working on conduits in a submerged location, said method comprising: independently exerting a series of longitudinally spaced independent and transversely directed forces on each of two spaced conduit means to adjust the alignment thereof; isolating said aligned conduit means in a gaseous environment; selectively adjusting the humidity and temperature of the working environment; during said working, exerting jacking force from a submerged surface on said conduit means to adjust and maintain the alignment; and during said working, sequentially exerting said forces on said conduit means under the control located externally and then internally of said working environment. 